Cummins ISB4.5 CM2150 Fault Code: 2357 PID: SPN: 2971 FMI: 7 EGR Valve Control Circuit – Mechanical System Not Responding or Out of Adjustment.

Circuit Description
The engine control module (ECM) controls the EGR valve, opening and closing it based on various operating conditions. The EGR valve is opened and closed by a DC motor that receives voltage from the ECM on the EGR valve motor signal (+) and (-) circuits. To open the valve, the motor receives voltage on the EGR valve motor signal (+) circuit. To close the valve, the motor receives voltage on the EGR valve motor signal (-) circuit.

Component Location
The EGR valve is located on the exhaust side of the engine and is attached to the EGR cooler, which is mounted to the exhaust manifold

Conditions for Running the Diagnostics
This diagnostic runs continuously when the engine is operating, and the EGR valve is being commanded to move. The ECM is programmed to do a sweep of the EGR valve at key ON, during which this diagnostic will run as well.

Conditions for Setting the Fault Codes
This fault code is set when the duty cycle required to open the EGR valve is greater than 95 percent for 3 seconds.

The fault code will be inactive at key ON. It will only go active if the EGR valve is commanded open and the EGR valve is unable to move to the commanded position.

Action Taken When the Fault Code is Active
-The ECM illuminates the amber CHECK ENGINE lamp and/or the malfunction indicator lamp (MIL) immediately when the diagnostic runs and fails.
-The EGR valve operation will be disabled

Conditions for Clearing the Fault Code
-The fault code will always be inactive at key ON. To validate the repair, start and idle the engine for 1 minute. If the fault code does not become active again, the repair has been validated.
-The ECM will turn off the MIL after 3 consecutive ignition cycles that the diagnostic runs and passes.
-This fault code can also be cleared with the INSITE™ electronic service tool

Shop Talk
The ECM monitors the duty cycle of the valve and logs a fault code if the duty cycle is too high. This fault is always set inactive when the keyswitch is turned ON. If there is a failure, the fault code will not be set active until the valve has been actuated. For these reasons, this troubleshooting tree must be used for both active and inactive fault codes.

Possible Causes
-Damaged EGR valve position sensor; mechanical or electrical damage
-EGR valve assembly damage requiring a high current to operate the valve, such as a stuck or sticking valve.

NOTE: Do not supply 12V to the EGR valve position sensor, or short the EGR valve motor wires to the EGR valve position sensor. The EGR valve position is rated at 5V, and sensor damage may occur.